gas: Enhance arch-specific SFrame configuration descriptions

Explicitly mention "SFrame" in the descriptions for the architecture-
specific SFrame configuration macros, variables, and functions.

Use the term "frame pointer" (FP) instead of "base pointer". This aligns
with the terminology used in the SFrame specification. Additionally it
helps not to confuse "base-pointer register" with the term "BASE_REG"
used in the specification to denote either the SP or FP register.

Specify what the SFRAME_CFA_*_REG register numbers are used for:
- SP (stack pointer): CFA tracking
- FP (frame pointer): CFA and FP tracking
- RA (return address): RA tracking

Align the descriptions for definitions in the source files to the
declarations in the header files.

gas/
	* config/tc-aarch64.h: Enhance architecture-specific SFrame
	configuration descriptions.
	* config/tc-aarch64.c: Likewise.
	* config/tc-i386.h: Likewise.
	* config/tc-i386.c: Likewise.

Signed-off-by: Jens Remus <jremus@linux.ibm.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c
index a83ce21..9539957 100644
--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -11987,6 +11987,7 @@ x86_cleanup (void)
     subseg_set (seg, subseg);
 }
 
+/* Whether SFrame stack trace info is supported.  */
 bool
 x86_support_sframe_p (void)
 {
@@ -11994,6 +11995,7 @@ x86_support_sframe_p (void)
   return (x86_elf_abi == X86_64_ABI);
 }
 
+/* Whether SFrame return address tracking is needed.  */
 bool
 x86_sframe_ra_tracking_p (void)
 {
@@ -12003,6 +12005,8 @@ x86_sframe_ra_tracking_p (void)
   return false;
 }
 
+/* The fixed offset from CFA for SFrame to recover the return address.
+   (useful only when SFrame RA tracking is not needed).  */
 offsetT
 x86_sframe_cfa_ra_offset (void)
 {
@@ -12010,6 +12014,7 @@ x86_sframe_cfa_ra_offset (void)
   return (offsetT) -8;
 }
 
+/* The abi/arch indentifier for SFrame.  */
 unsigned char
 x86_sframe_get_abi_arch (void)
 {